Electric control for door opening and closing mechanisms



June 26, 1951 B. A. ANDREWS 2,558,032

ELECTRIC CONTROL FOR DOOR OPENING AND CLOSING MECHANISMS Filed Nov. 22, 1948 Patented June 26, I951 ELECTRIC CONTROL FOR DOOR. OPENING AND- CLOSING MECHANISMS Boley A. Andrews,.Kansas City, Kane, assignor, by mesneassignments, toThe Vendo Company, .Kansas City, Mo., a corporation of Missouri Application'November 22, 1948, Serial No. 61,474

2 Claims. I

This invention has to do generally with door actuating mechanism and more particularly to an electric circuit for" automatically controlling the operation of such mechanism to move a door to and from a closed position through the mere expedient of causing the energization of an electric motor or like prime mover.

By way of explanation, there are today many diiferent types of mechanical contrivances obtainable upon the open market capable of moving a closure such as a garage door, toward and from an open position, and in my co-pending application, filed on even date herewith and entitled Motor Actuated Door Operator, a particular type of such door operating means is disclosed.

It is to be understood at the outset that the electric circuit forming the subjectmatter hereof, is not necessarily limited in its operation to use with door mechanism such as that set forth in my co-pending application, but may be used generally with door actuating structures having the minimum requirements to be hereinafter set forth fi ly, the mechanismthat interconnects the electric motor hereinafter mentioned, with the door to be actuated, has not been illustrated. .In the same manner, certain switches to be referred to during the course: of the following specification, may be operated-by theoloor itself in conventionalmanners and such switch operating means has also been eliminated from this disclosure.

It is the primary object of the present.invention to provide an electric circuit for controlling theoperation of door actuatingmechanism having. as a part thereof, a pair of relays for closing and opening the door respectively, said relays, together with other parts of the circuit,.being.so arranged that only one of the relays can be energized at one time.

Another important object of the present invention is the provision of electriccontrolmeans for dooropening and closing mechanisms having a pair of switch assemblies for deenergizing the electrical circuit-when the door reaches theends of its path of travel in the closed and open positions respectively, thecircuit. being so arranged that movement of only one of the door operated switches during the cycle of operation will have eiTect upon the circuit itself.

A further object of the present invention is to provide anelectric circuit of the abovementioned character having timing meansinterposed therein and operable only when the door moves-toward one end of its path of travelfor automatically deenergizing the entire circuit after a predetermined period of time if, for some reason, the door doesnot reach said end of its path of travel in the normal lapse of time.

Other objects of the present invention will be made clear as the following specification progresses, reference being had to the accompanying drawing, wherein the single figure is a schematic wiring diagram of an electric control for door opening and closing mechanisms made in accordance with the pr sent invention.

In the circuit illustrated by the drawing, there is illustrated an armature l0 and a field coil l2 forming a part of a high speed, universal, reversible electric motor. This motor may be coupled with any suitable mechanism to a door to be actuated thereby for moving said door to an open position when the motor shaft rotates in one direction and moving the door to a closed position when the motor shaft rotates in the opposite direction.

As above mentioned, the particular type of mechanism that is utilized for interconnecting the motor with the door, is of no consequence to the present invention and since the same may embody any conventional structure well within the knowledge of those skilled in the art, the same has not been illustrated and will not be further described.

The electrical circuit of the drawing also includes alimit switch 14 that is disposed for movement toward and from a closed position by the aforesaid door opening and closing mechanism,

coupled with the electric motor formed by armature Ill and field [2. While it is contemplated that the switch I i be so arranged within the door actuating mechanism as to automatically open whenever an overload occurs in the door itself or the mechanical parts connected therewith, it is sufiicient to note that for the purpose of the present invention, switch hi may be coupled simply with the door itself ior movement-t0 the open position when the door reaches the closed position and for immediatelyopening when the door commences its movement toward the open position.

A second switch 13 operates in much the same manner so as to be disposed in the closed position when the door is closed and in the open position when the door is open.

.By way of clarification, the switch M is open and the switch It is closed as illustrated in the drawing, whenever the door is closed. Conversely, when the door is in the open position, the switch It is closed and the switch It opens.

In addition to the electrical components of the circuit thus far mentioned, there is provided a door opening relay, broadly designated by the numeral I8, a door closing relay broadly designated by the numeral 28, a switch 22, a thermal switch 24, a switch 26 ganged with the switch IS, a lamp 28 and a transformer 38.

Transformer 38 is provided with a primary winding 32 and a secondary coil 34. The relay I8 has a coil 36 and a plurality of switches 38, 40, 42 and 44. It is to be noted that the switches 38, 42 and 4% of relay I8 are normally open, whereas the switch 48 thereof is normally closed.

The relay 20 is identical with the relay I8 and includes a coil 48 and a number of switches 48, 58, 52 and 54. Here again, the switches 48, 52 and 54 are normally open, whereas the switch of relay 20 is normally closed.

Thermal switch 26 has a heating element 56 and a contact arm 58. The switch 22 is illustrated as an ordinary push-button type of make and break mechanism that may well be conveniently disposed adajacent the garage doors. Obviously, it is within the scope of this invention that the switch 22 be operated by any one of the present day automatic garage door opening devices that includes an ultrasonic whistle and a radio receiver for receiving such sounds and causing the closing of switch 22.

A pair of lead lines 58 and 68 have connection with a source of alternating current electrical energy (not shown) for supplying the primary 22 of transformer 28 as well as other electrical components in the manner about to be described. Secondary 34 of transformer 3|] receives energy from primary 32, the latter being connected with lead lines 58 and 60 by wires 62 and 82 respectively.

Assuming first that the door to be controlled by the circuit hereof, is in the closed position wherein the switch I6 is closed and the switch I4 is open as illustrated, the circuit for energizing the door opening relay I8 after closing of switch 22, is traceable as follows:

From secondary 34 through lines 66, 8B and I8, closed switch 22, lines I2, M, I6 and I8, coil 38 of relay I8, line 82, normally closed switch 59 of relay 28, lines 82 and 84, closed switch I6 and wire 88 to secondary 34.

Energization of coil 35 of relay I8 will move the switches 38, 22 and 44 from the normally open position to a closed position, and also open the normally closed switch 48. Closing of the switch 38 operates to hold the relay IB energized while the door moves from the closed position to the open position irrespective of reopening of switch 22, through the following circuit:

From secondary 34 of transformer through wires 65 and 88, closed switch 38 of relay I8, wires 98 and i8, coil 28 of relay I8, wire 80, closed switch 58 of relay 28, wires 82 and 84, closed switch I6 and wire 88 to secondary 34.

With the relay I8 thus held in the closed energized condition, the circuit for energizing the armature Ill and field I2 of the electric motor, to cause rotation of the drive shaft of such motor in one direction to open the door, is traced as follows:

From lead line 58 through wire 92, normally closed contact arm 58, wire 94, closed switch 42 of relay I8, wires 98, 98 and IE8, armature I8, wires I82, I84 and I86, closedswitch 44 of relay I 8, wires I08 and H0, field I2 and wires H2 and IM to lead line 88.

As above explained, when the door moves to 4 the fully open position, the switch I6 is automatically opened. Since the circuit above traced through switch 38 for holding relay I8 closed, includes this switch I6, opening of the latter will obviously deenergize the coil 36 of relay I8 with a resultant re-opening of switches 22 and 44 that in turn deenergize the circuit through armature I 8 and field I2.

The electric motor will thus discontinue its operation and the door will come to rest in the fully opened position until such time as the push-button 22 is again moved to a circuit c1osing position.

It is to be noted at this point that movement of the switch It to the open position also moves the switch 28 to a position closing a circuit through the lamp 28, this circuit being traced as follows:

From primary 32 of transformer 32, through lines 62, H2 and H5, lamp 28, wire H3, closed switch 26 and line I22 to secondary 84.

It is contemplated that the lamp 28 be positioned next adjacent the door to be controlled by the present invention for lighting the garage and runway thereto while the door is in the open position.

Remembering that initial movement of the door from the fully closed position toward the open position, causes the switch 14 to move to a closed position, the circuits for causing the door to return to a closed position upon initial closing of switch 22, are traced as follows:

From secondary 34 through wires 66, 63 and 18, closed switch 22, wire I2, coil 45 of relay 28, wire I22, normally closed switch 48 of relay I8, wire I22, closed switch I4 and wires I26 and 86 to secondary 38.

This just mentioned circuit through coil 46, will cause the switch 58 of relay 20 to open and will close the switches 48, 52 and 52 of relay 20. Closing of the switch 48 will hold the coil 86 energized, irrespective of re-opening of switch 22 through the following circuit:

From secondary 34 of transformer 30, through wires 66 and 68, closed switch 48, wires I28 and M, coil 46, wire I22, normally closed switch 40 of relay I8, wire I24, closed switch I4 and wires I26 and 88 to secondary 34.

With the relay 2!! thus held in the closed position, the circuit through armature i0 and field I2 of the electric motor capable of rotating the drive shaft thereof in a reversed direction for returnin the door to the closed position, is traced as follows: 7

From lead 58 through wire 92, normally closed contact arm 58 of thermal switch 24, wires 94 and I30, closed switch 52, wires I32 and H52, armature I0, wires I and I34, closed switch 54, wires I36 and III], field I2 and wires H2 and H4 to lead 60.

As the door moves from the open position toward the closed position, the switch I6 is reopened and when the door reaches the fully closed position, the switch I4 will re-open. Since switch I4 is within the circuit through switch 48 for holding coil 46 energized, opening of such switch I4 will obviously deenergize relay 2!] and stop the motor that includes armature I8 and field I2. Deenergization of the motor is occasioned by reopening of switches 52 and 54 of relay 20.

- It is also apparent at this point that if the switch I4 is operably associated with mechanism capable of moving the switch I4 to an open position, whenever an overload occurs with respect-to the door movement, the circuit will be automatically deenergized through such opening of switch l4, stopping further movement of the door toward the closed position.

The thermal switch 24 is of conventional character and is provided within the circuit as a safety feature for automaticall deenergizing the motor circuit, if for some reason the motor stalls during the door opening operation. Switch 26 is so timed as to deenergize the motor circuit after an expiration of time, preferably equal to twice the normal door opening time. The heating element 56 is so arranged as to be energized only while the door is moving toward the open position and such operation is accomplished by interposing the element 56 within a circuit that includes the switch 50 of relay 20. Thus, when the normally closed switch 50 of rela is opened through energization of the relay 20 to move the door to the closed position, element 56 will not heat. However, when switch 22 is closed to operate relay I8, the element 56 is energized through the following circuit:

From secondary 34 of transformer 30, through switch l6 (that is in the closed position while the door moves toward the open position), wires 84 and 82, closed switch 50, wires 86 and I38, element 56, wires M0, 18 and 98, switch 38 (closed by virtue of energization of coil and wires 86 and 66 to secondary 34. When the element 56 reaches a sufficiently heated condition, contact arm 58 will be caused to open and thereby deenergize the circuit through the electric motor that operates to cause the door to move to the open position.

It is apparent from the foregoing that closing of switch 22, whenever the switch I4 is open and the switch I6 is closed, will always cause the door to move from the open position to the closed position. Conversely, closing of the switch 22 whenever the switch I4 is closed and the switch l6 open, will cause the door to move from the closed position to the open position.

It is also clear that when the door closes to thereby open switch M, such door will not immediately move toward the open position until switch 22 is again closed because of the fact that closing of switch [6 cannot cause energization of the motor circuit in the absence of closing of switch 22. In the same way, closing of switch M as the door commences its opening movement, cannot close the circuit as long as the switch 22 is open.

With the relays l8 and 20 interconnected in the manner just above set forth, a further safety featureis provided preventing any operational effects if the operator should hold the switch 22 in the closed position while the door moves through its cycle. For instance, closing of switch 22 for energizing relay [8, automatically opens the switch 40 of relay l8 and as soon as this action takes place. there is no open circuit through coil and switch 22 even though the latter is held closed because of the fact that switch 40 of relay I8 is open. Conversely, closing of the switch 22 to energize coil 46 will automatically open the switch 50 and when this last mentioned switch opens, a holding of the switch 22 in a closed position will not energize the coil 36 because of the fact that the circuit for coil 36 includes the open switch 50.

Manifestly, all of the safety precautions that are necessary in door operating mechanisms have been provided in the electric circuit above described and forming the subject matter hereof.

Since switches M and 55 are both closed while the door is intermediate its path of travel in either direction of movement, the relay structure hereof serves as a safety means, preventing any attempt of the circuit to rotate the motor armature in both directions simultaneously.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An electric control comprising a reversible electric motor; an electric circuit for said motor; a pair of normally open make and break mechanisms in said circuit, adapted when alternately closed to couple said circuit with said motor in reverse relationship respectively; an electromagnet actuator for each of said mechanisms respectively; a control circuit and a holding circuit for each of said actuators respectively, said control circuits being connected in parallel and having a control switch common thereto; a normally open switch in one of said control circuits; a normally open switch in the other of said control circuits; and a normally closed contactor in series with each of said control circuits respectively, said contactors each being disposed for control by the actuator of the opposite control circuit respectively whereby each control circuit respectively is deenergized as the other control circuit is held closed by its corresponding holding circuit.

2. An electric control comprising a reversible electric motor; an electric circuit for said motor; a pair of normally open make and break mechanisms in said circuit, adapted when alternately closed to couple said circuit with said motor in reverse relationship respectively; an electromagnet actuator for each of said mechanisms respectively; a control circuit and a holding circuit for each of said actuators respectively, said control circuits being connected in parallel and having a control switch common thereto; a normally open switch in one of said control circuits; a normally open switch in the other of said control circuits; a normally closed contactor in series with each of said control circuits respectively, said contactors each being disposed for control by the actuator of the opposite control circuit respectively whereby each control circuit respectively is deenergized as the other control circuit is held closed by its corresponding holding circuit; and thermo control means for deenergizing said motor circuit after either control circuit has been held closed for a predetermined period of time.

BOLEY A. ANDREWS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,640,559 Bouton Aug. 30, 1927 2,342,597 Opalek Feb. 22, 1944 

